The present invention relates to a vacuum coupling system, and more specifically, to a vacuum coupling system for connecting a vacuum coupling to a valve mechanism of an integral structure (hereinafter referred to as "shell") formed by uniting a semiconductor wafer (hereinafter referred to as "wafer"), a contactor, and a wafer holder (hereinafter referred to as "water chuck" by vacuum suction. Further specifically, the invention relates to a vacuum coupling system for connecting a vacuum coupling to a valve mechanism of a shell, which is formed by attracting a wafer and a contactor on a wafer chuck by vacuum suction, in conducting various tests on a semiconductor device (hereinafter referred to as "IC chip") that is formed on the wafer.
In a conventional reliability test, potential defects in packaged IC chips are detected by applying thermal and electrical stresses to the chips so that defective IC chips can be removed. With the development of smaller-sized, higher-function electrical equipment, IC chips have been miniaturized and enhanced in the degree of integration. Recently, there have been developed various mounting techniques for further miniaturization of semiconductor products. For example, a novel mounting technique has been developed for mounting unpackaged or bare IC chips.
Bare chips to be put on the market should be subjected to a reliability test. Conventional reliability testers have some problems on electrical connections between bare chips and sockets, for example. Besides, handling small bare chips is very troublesome and possibly entails an increase in testing cost.
Reliability testing techniques for testing IC chips on a wafer are proposed in Jpn. Pat. Appln. KOKAI Publications Nos. 7-231019, 8-5666, and 8-340030, for example. According to the techniques proposed in the former two publications, wafers and contactors, such as probe sheets, are securely collectively brought into contact with one another to be united without being thermally affected. Each contactor includes a contact terminal that electrically touches predetermined electrodes of a plurality of IC chips on each wafer and an external terminal connected to the contact terminal. The contactor is stuck fast on the wafer so that the contact terminal is in contact with the predetermined electrodes.
In an electrical property test or reliability test for IC chips on a wafer, it is essential to form and maintain the shell in which the contactor, wafer, and wafer holder are securely united together.
Conventionally, various techniques are proposed as methods for collectively bringing wafers and contactors into contact with one another. However, there is no practical apparatus for automatically loading shells into a reliability tester.
The inventor hereof proposed, in Jpn. Pat. Appln. Publication No. 9-318920, a wafer temperature control device and a wafer storage chamber that can maintain a given testing temperature to improve the reliability of a reliability test. However, a technique for automatically loading shells into the wafer storage chamber to automate the reliability test is on its way to development.